This invention relates to methods and apparatus for handling selected objects, and more particularly relates to improved methods and apparatus for manipulating objects in hostile or otherwise disadvantageous environments or conditions.
It is well known that it has been proposed to place a habitable "Space Station" in an orbital path around the earth, and to construct such station from parts or components which will be separately ferried up from the surface of the earth and thereafter assembled at a selected location along said orbital path. Upon consideration of the problems inherently attending such a task, it will be immediately apparent that a suitable manipulating system will be required for securing and thereafter maneuvering such components into a position whereby they may be suitably interconnected.
There are, of course, many different types of systems and techniques for manipulating and treating articles under conventional circumstances. For various reasons hereinafter reviewed in detail, none of these prior art systems and techniques are suitable for the above-identified purpose.
There are many situations when, for various different reasons, special methods or apparatus are either preferred or required in order to handle a particular object. For example, the object itself may be too heavy to be manipulated, it may be dangerous to approach and manually handle, or the object may be positioned in an inaccessible location or a hostile environment. Alternatively, the object may be located in an assembly line or the like, wherein a particular manipulation is sought to be performed by one or more steps in an automated process.
More particularly, it is well known that the prior art is replete with examples of different forms of apparatus for manipulating objects for differet purposes under different conditions. For example, Ando et al, (U.S. Pat. No. 3,888,360) details a programmable robot having a movable hose upon which a manipulator arm is attached. Movement of equipment through utilization of said configuration is limited, however, since base motion is restricted to rectilinear motion along three orthogonal axes.
Further, Haase (U.S. Pat. No. 3,437,223), Hainer (U.S. Pat. No. 3,262,593) and Insolio et al (U.S. Pat. No. 2,983,391), disclose a carrier block, a support structure, and a trolley element from which a manipulator arm extends. These carrier bases are confined to movement within only one plane.
It will be apparent that, in many if not all such examples, it is convenient, if not essential, that the operator of the manipulating device be situated in a location which is either remote from the initial position of the object is to be is remote from the position to which the object being handled, moved, or both. See, for example, Blaseck (U.S. Pat. No. 4,527,934) which is a remotely-controlled manipulator attached to a support means which moves vertically on a guide column. This guide column is mounted on upper and lower rotatable plates in order to achieve rotation of the guide column about the vertical axes of the plates. The rotation of the guide column, however, is restricted to that direction of rotation which is parallel to the rotational axes of the plates depicted in the reference. This creates a critical limitation on the operator's freedom of movement insofar as his ability to handle the manipulating device is concerned, and it requires that the operator be located in close proximity to the manipulating.
All of these techniques and devices are, of course, generally suitable for their intended purposes. It will be noted, however, that there is a common characteristic with respect to these and all other similar manipulating devices and techniques in the prior art; i.e., the manipulating techniques and devices in the prior art are all designed for use under conditions wherein the operator is situated in a relatively normal environment, and wherein it is only the object sought to be manipulated which is situated in an abnormal environment. In other words, all of the prior art devices anticipate that the operator will be capable of full freedom of movement insofar as his ability to handle the manipulating device is concerned.
The present invention is directed to an application which is completely different from those hereinbefore discussed with respect to prior art methods and apparatus. More particularly, there are plans to construct an orbiting "Space Station" from components and sub-assemblies which are separately ferried to the orbital location where they are to be be assembled. Accordingly, it will be apparent that such a project will require the means for maneuvering objects of various different shapes and sizes under the most adverse conditions. Both the operator as well as the object to be handled are situated in the same hostile environment and under conditions wherein the operator is severly limited in his freedom of action. Such a maneuvering device or means must be capable of seizing and moving these various components in almost any direction relative to the position of the operator, and over extended distances of travel. This maneuvering device itself must also be capable of being carried into orbit by transport means and techniques now available.
It has previously been proposed to employ a manipulating device for use on the Space Station known as a "Mobile Remote Manipulating System" (MRMS). This device is capable of seizing and moving an object in two orthogonal directions relative to its orbital location on the station. More particularly, the MRMS is movably secured to the nodes of a truss-like member of the station and a push-pull mechanism provides an "inch worm" translation of the MRMS along the truss. In addition, a self-contained power unit or supply is required for moving the device to various locations along the station.
Although the so-called MRMS device is clearly more suitable for its intended purpose than are any of the techniques and devices depicted in the aforementioned prior art, it will nevertheless be apparent that the MRMS is also subject to certain limitations. To begin with, it can be seen that the MRMS is only capable of moving an object along one of two orthogonal directions, relative to its orbital location, at a time. This increases, considerably, the amount of time required to transport a payload between the transport vehicle and the station, or between two points along the station. The reach capability of the MRMS is also limited to the extended length of the manipulator arm. This limitation makes it difficult to use the MRMS as a berthing aid.
Further, since the MRMS is designed to ride along the truss members of the space station, it is necessary to avoid obstructing the travel path of the device. This clearly limits the amount of useful payload attachment space available If any part of the structure on which the MRMS travels is damaged or obstructed, the directions in which the device can move will also be severely restricted.
These and other disadvantages of, or limitations on, the capabilities of the prior art are overcome or substantially mitigated with the present invention. Improved methods and apparatus are herewith provided for manipulating objects of varying size and shape under extraordinarily disadvantageous operating conditions.